ML19276G892

Submits Info Re Deficiency Reported 790731.Component W-104 on 7300 Series Signal Comparator Cards Sometimes Fails, Preventing Bistable from Performing Function.Components Will Be Replaced

ML19276G892
Person / Time
Site:	North Anna
Issue date:	08/06/1979
From:	Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
632, NUDOCS 7908280559
Download: ML19276G892 (2)

Text

._ . _ . __ _

?$C11S. p VIRorarA Er.ECTRrc AND power pOMPANY '

H r caw on n.Va zo rn :A soebt l

. August 6, 1979 $*:. '

'.~~.

.f5 O ~~ a Mr. James P. O'Reilly, Director Serial No. 632 cc -

Office of Inspection and Eaforcement P0/RMT:cej U. S. Nuclear Regulatory Commission Docket No. 50-338 7  :

License No. NPF-4 C Region II **

101 Marietta Street, Suite 3100 Atlanta, Georgia 30303 $

Dear Mr. O'Reilly:

Under the provisions of 10CFR21, NRC Region II was notified on July 31, 1979 that a potentf al significant deficiency or substantial safety hazard existed at North Anna Power Station Unit No. 1.

In accordance with the reporting requirements of the above regulations, the following infor=ation is subm.'tted :

A. Name and address of reporting individual:

C. M. Stallings Virginia Electric and Power Company P. O. Box 26666 Richmond, Virginia 23261 B. Facility, activity, and/or component af fected :

Westinghouse 7300 Process NAL Cards .

C. Name of firm supplying the component, activity cr service:

Westinghouse Electric Corporation Computer and Instrumentation Division 200 Beta Drive O'Hara Township, Pittsburg, Pa. 15238 D. Description of defect, deficiency, or failure to comply:

Compone:.e W-104 (Dual Peripheral D. iver and 2 NPN Output Transistors) on 7300 series signal comparator (NAL) cards sometimes f ails in a shorted condition thereby preventing the associated bistable f om performing its intended function.

WVO t

[b t 190530 OWidAL COPY 7908080Sfp

4 ,- ,

2 Vinoista ELzcTasc ano Powas Courawv to Mr. Enrold R. Denton E. Date of determination of reportability:

'uly 30, 19 79 F. Similar components, activities or services:

Unit 2 uses identical process cards in its protection system.

G. Corrective Action which has been, or is being, or will be taken, the individual responsible and the length of time to complete the action:

When the components become available, the Vepco Instrument Department will remove NAL cards in both units and replace each W-104 component with an upgraded I.C. If upgraded spare cards are available, they will be installed in place of the defective NAL cards and the defective cards will be modified to be used at a later date if needed.

H. Other information:

Any additional information regarding the above topic will be submitted in the Licensee Event Report.

Should you require further information, please contact this office.

Very truly yours, b', , hhlduir;3 C. M. Stallings Vice President-Power Supply and Production Operations cc: Mr. Victor Stello, Director (3 copies)

Office of Inspection and Enforcement 2041 ill

. , . . .